Meeting Announcement
We are pleased to announce the 22nd meeting of the CEOS Atmospheric Composition Virtual Constellation (AC-VC): The meeting will take place on 1-4 June 2026 in the beautiful town of Leiden in the Netherlands and is co-hosted by the Space Research Organisation Netherlands (SRON) and the European Space Agency (ESA).
The meeting will be held jointly with the CEOS Working Group on Calibration & Validation (WGCV) / Atmospheric Composition Subgroup (ACSG).
We invite you to register and participate to the CEOS AC-VC #22 / WGCV-ACSG Joint Meeting.This meeting brings together the AC‑VC and ACSG communities for updates, coordination, and expert discussions. Explore the sections below for programme details, participation options, and registration information.
Please note, we encourage physical attendance to stimulate active participation and interaction.
The deadline for registration is Sunday, 17 May 2026.
Scientific Programme
CEOS AC-VC #22 / WGCV-ACSG Joint Meeting 2026
👉 All presentations will be made available on the CEOS AC-VC website
Agenda & Logistics
👉 Detailed Agenda & Meeting Info
Venue
SRON is a leading international research institute operating at the forefront of space research to address fundamental questions about the cosmos and the Earth’s environment. As the primary space research institute in the Netherlands, SRON serves as a focal point for coordinating and conducting cutting-edge research in astrophysics and Earth science from space.
At the international level, collaboration and cooperation are crucial for advancing space research. Organisations like ESA, NASA, and JAXA foster international partnerships through joint missions, data sharing, and scientific collaborations. SRON operates as a key player within this landscape by bringing together scientific expertise, developing innovative technologies, and the design and construction of advanced instrumentation.
SRON acts as a hub for space-based research and cutting-edge instrument development. SRON’s contributions enable Dutch astronomers to participate in international collaborations, publish ground-breaking research and contribute to the global understanding of the universe. Similarly, within the Earth observation community, SRON plays a crucial role in advancing Dutch expertise in studying and monitoring Earth’s atmosphere and climate. The institute develops advanced satellite instruments and analysis techniques that contribute to the country’s capabilities in Earth observation. SRON’s research and data provide valuable insights into climate change, air quality and environmental processes, enabling evidence-based efforts in environmental management, policy making and sustainable development.
SRON has two locations in the Netherlands, Groningen and Leiden. For this event, you are invited to come to our Leiden office, Niels Bohrweg 4, 2333 CA Leiden, the Netherlands.
Registration
Registration for CEOS AC‑VC #22 / WGCV‑ACSG in Leiden will open on Tuesday, 21 April. Participation is free of charge.
Onsite Participation
Onsite attendance is strongly encouraged to ensure the best engagement with experts and working groups present.
- Deadline to register for onsite participation: Sunday, 17 May 2026
Catering during the meeting will be entirely vegetarian and vegan
Online Participation
If you are unable to join in person, you may attend the meeting online.
- Deadline to register for online attendance: Sunday, 17 May 2026
Cancellations
In case of cancellations, please contact SRON: sron_events@sron.nl
Travel Information
Leiden can be reached by plane (via Schiphol airport) and by train (via the main station ‘Leiden Centraal’).
Public Transport
SRON Leiden is easily accessible by public transport. From Leiden Centraal, take a bus towards the Leiden Bio Science Park and get off at the “Niels Bohrweg” stop. It’s only a short walk from the stop to SRON.
Parking at SRON
Visitors can park their cars at the parking lot on Ehrenfestweg 1, 2333 CC LEIDEN just a 6 minute walk from SRON. This parking lot is equipped with charging stations for electric vehicles. The parking fee is €2,30 /hr (max 21€ /day).
Navigate to ‘Ehrenfestweg Leiden,’ and as you enter the street, you will see the parking lot on the left, in the side street (marked with a red line on the map). After parking, follow the walking route (marked in green) from the parking garage to SRON.
The Netherlands are part of the Schengen area. In case you are not sure whether you need a visa, you may consult https://www.netherlandsworldwide.nl/visa-the-netherlands or https://ind.nl/en/short-stay/short-stay-holiday-or-business-visa.
Accommodation
Hilton hotel Leiden 550 m: Hotels in Leiden - Hilton Garden Inn Leiden
Fletcher welness Leiden 2km: Fletcher Wellness-Hotel Leiden – Fletcher Hotels (wellnesshotelleiden.nl)
Golden Tulip 2,5km: Golden Tulip Leiden Centre Hotel - 4 sterren
Haagse Schouw- Hotel Leiden 1,9km: Van der Valk Hotel Leiden - Valk Exclusief
Bastion Oegstgeest 1,6km: https://www.bastionhotels.com/en-gb/hotels/hotel-oegstgeest
Boutique Hotel 3,5km: Boutique hotels van Leyden
City Hotel Rembrandt 2,7km: Rembrandt City Hotel Leiden, Leiden
Intercity Hotel 2,4km: IntercityHotel Leiden| H Rewards
Background
The Committee on Earth Observation Satellites (CEOS) was established to coordinate and harmonize Earth observations to make it easier for the user community to access and use data. The CEOS virtual constellations embrace missions that have been conceived by the various space agencies. AC-VC aims at fostering scientific and technical cooperation among space agencies active in the spaceborne observation of atmospheric composition, focusing on trace gases and aerosol. The goal of WGCV/ACSG is to ensure the accurate and traceable calibration of remotely-sensed atmospheric composition radiance data and validation of atmospheric composition products.
ESA is dedicated to the peaceful exploration and use of space for the benefit of everyone. ESA develops a wide range of Earth observation missions: from Earth Explorers that enable new science and extend the understanding of our environment to operational missions that feed environment information services.
SRON conducts satellite-based observations of the Earth’s atmosphere, with a primary focus on greenhouse gases, aerosols, and atmospheric pollutants. The quantification and spatial mapping of methane (CH₄) and carbon dioxide (CO₂) emission hotspots contribute to assessing progress toward the emission reduction targets established under the Paris Agreement. Research on atmospheric aerosols aims to reduce uncertainties regarding their radiative effects and overall role in the climate system. Furthermore, trace gases such as carbon monoxide (CO) serve as indicators of biomass burning and anthropogenic emissions, thereby elucidating the impact of wildfires and urban air pollution.
CEOS AC-VC meetings are held on a yearly basis. The meetings in the recent years since Covid-19 were held in Takamatsu, Japan (2025), College Park, MD, USA (2024) and Brussels, Belgium (2023).
Organising Committee
Local Hosts
- Jochen Landgraf (SRON)
- Ben Veihelmann (ESA)
- Janneke van Duijn (SRON Secretariat)
- Tessa Rowbottom (ESA Conference Bureau)
AC-VC Leadership
- Ben Veihelmann (ESA), Co-Chair
- Emma Knowland (NASA), Co-Chair
- Hiroshi Tanimoto (NIES), Co-Chair, greenhouse gases
- Shobha Kondragunta (NOAA), aerosol, wildfire and smoke
- Diego Loyola (DLR), ozone, water
- Jean-Christopher Lambert, WGCV-ACSG Chair
Social Event
Join us for the AC-VC conference social event in the beautiful setting of the Hortus Botanicus in Leiden.
Please note that all catering provided during the meeting, including the social event dinner, will be fully vegetarian and vegan.
Participants who have food allergies (not dietary wishes or preferences) must inform us during registration for:
The evening programme includes a reception and dinner, after which participants are invited on guided tours of the historic gardens and the Old Observatory. This special after hours experience offers a rare chance to explore two of Leiden’s most iconic locations in an intimate and memorable setting.
Programme
Travel Information
It is approximately a 35 minute walk through the city of Leiden to reach the Hortus Botanicus. Public transportation is also available: you can travel from SRON to Leiden Central Station, and from there it is a 15 minute walk to the Hortus Botanicus.